Shugoshin1 may play important roles in separation of homologous chromosomes and sister chromatids during mouse oocyte meiosis.
BACKGROUND
Homologous chromosomes separate in meiosis I and sister chromatids separate in meiosis II, generating haploid gametes. To address the question why sister chromatids do not separate in meiosis I, we explored the roles of Shogoshin1 (Sgo1) in chromosome separation during oocyte meiosis.


RESULTS
Sgo1 function was evaluated by exogenous overexpression to enhance its roles and RNAi to suppress its roles during two meioses of mouse oocytes. Immunocytochemistry and chromosome spread were used to evaluate phenotypes. The exogenous Sgo1 overexpression kept homologous chromosomes and sister chromatids not to separate in meiosis I and meiosis II, respectively, while the Sgo1 RNAi promoted premature separation of sister chromatids.


CONCLUSIONS
Our results reveal that prevention of premature separation of sister chromatids in meiosis I requires the retention of centromeric Sgo1, while normal separation of sister chromatids in meiosis II requires loss of centromeric Sgo1.
Yin
Shen
S
State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
Ai
Jun-Shu
JS
Shi
Li-Hong
LH
Wei
Liang
L
Yuan
Ju
J
Ouyang
Ying-Chun
YC
Hou
Yi
Y
Chen
Da-Yuan
DY
Schatten
Heide
H
Sun
Qing-Yuan
QY
D000818:Animals; D018797:Cell Cycle Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002503:Centromere / Q000187:drug effects / Q000378:metabolism; D002842:Chromatids / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D020090:Chromosome Segregation / Q000187:drug effects / Q000235:genetics*; D005260:Female; D008540:Meiosis / Q000187:drug effects / Q000235:genetics*; D051379:Mice; D008813:Mice, Inbred ICR; D009865:Oocytes / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D034741:RNA, Small Interfering / Q000494:pharmacology; D017385:Sequence Homology; D014018:Tissue Distribution; D014162:Transfection
D018797:Cell Cycle Proteins; D034741:RNA, Small Interfering; C527733:shugoshin protein, mouse